Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations are all neutral (false), so the description carries the disclosure burden. It reveals that the call returns a thread_id, status, next_action, poll_after_seconds, and next_step, implying an async pattern. It also specifies a 16000-character limit for text, which is a concrete behavioral constraint. It does not detail side effects or error conditions, but it goes beyond annotations by describing the return contract and polling behavior.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.